CH 3 Quiz

A machine puts out 100 W of power for every 1000 W put into it. The efficiency of the machine is

10%

When Jean standing on slippery ice catches her leaping dog Daisy, the momentum of both Jean and Daisy after the catch is

Equal to their combined momentum before the catch

T OR F "Work involves the acceleration produced by a force on an object"

FALSE

An object may have potential energy because of its

Location

T OR F "Impulse is equal to change in momentum"

TRUE

To catch a fast-moving softball with your bare hand, you extend your hand forward just before the catch and then let the ball ride backward with your hand. Doing this reduces the catching

Time of catch is increased

Power is defined as the

Work done divided by the time to do the work

When a simple machine multiplies force, it decreases

distance moved

A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is

doubled

An object that has kinetic energy must be

moving